Use technology
and mathematics to improve investigations and communications

Formulate
and revise scientific explanations and models using logic and evidence

Recognize
and analyze alternative explanations and models

Communicate
and defend a scientific argument

Physical Science: Content Standard B:
All students should develop an understanding of:

Conservation
of energy and increase in disorder

Interactions
of energy and matter

Life Science:
Content Strand C: All students should develop an understanding of

Matter,
energy, and organization in living systems

Earth
and Space Science: Content Strand D:
All students should develop an understanding of:

Energy
in the earth system

Science
and Technology: Content Standard E:
All students should develop:

Abilities
of technological design

Understanding
about science and technology

Science in Personal and Social Perspectives:
Content Standard F:All students should develop understanding of:

Environmental
quality

Learning Objectives

Each student will:

Explain
how heat transfer mechanisms (conduction, convection and radiation)
and infiltration specifically influence the building envelope.

Give
examples of how the building envelope can be improved using an understanding
of heat transfer mechanisms.

Make and
test hypotheses about building envelope design and heat transfer mechanisms.

Background
Information, Vocabulary and Materials

Background
Information

In Lesson
1, we used a shipwrecked situation to construct a simple shelter. What
we were trying to deal with was in fact heat and moisture transfer into
and out of our structure.

In Lesson
2, we defined the structure itself, calling it the building envelope system
that includes subsystems of floor(s), walls, doors, windows, ceiling(s)
and roof(s). We then discussed how heat is either lost or gained through
these building envelope components through three heat transfer methods:
conduction, convection and radiation. We also introduced infiltration
and how it can bring in or remove hot or cold air and moisture.

Now, in Lesson
3, we will take two 50-minute class periods to investigate improving comfort
and productivity in our buildings by looking at how we can improve the
building envelope (how we can improve the building’s floor(s), walls,
doors, windows, ceiling(s) and roof(s)). Improving the envelope means
we are reducing or limiting conduction, convection and radiation and controlling
infiltration through the envelope components. These reductions in heat
transfer and uncontrolled airflow will in turn improve comfort and productivity
in buildings; this entire process can be thought of as improving building
performance.

Lesson 3
revolves around lab experiments that illustrate heat transfer methods
(Conduction Activities, Convection Activities and Radiation Activities).
Make sure to relate the results back to real buildings (e.g. your school
or house) and building performance.

You will
also be using the EnergyGauge USA® software to
show how annual energy use and cost decreases as the building envelope
is improved and infiltration is reduced. Review the Efficient Envelope
home on the software for your climate, especially noting the differences
in the insulation levels (between the Base home and Efficient Envelope
home) for the ceiling, walls, windows and floor, and Infiltration screen
Estimated Envelope Tightness. Note that the values used for the Efficient
Envelope house are typical of well insulated homes for the climate.

One other
note here is that a well insulated home in the South (of the United States)
does not require as much insulation as a well insulated home in the North.
This is because temperature differences between indoors and outdoors during
the winter are generally significantly greater in the North than in the
South. This concept is discussed in greater detail in the optional Advanced
Conduction Activities lesson.

If time permits
and it’s desired, you can add an extra day to discuss lab results,
test some optional insulating or reflective materials and/or spend more
time working with the software.

Vocabulary

Materials

Lesson
Procedures

Presenting
the Information

Have students
hand in their heat transfer mechanism homework from last class
(if assigned) and then discuss some of their examples.

Explain that
for this class period and the next, the class will be conducting a series
of 3 sets of experimental activities to investigate each of the 3 heat
transfer mechanisms.

Student Practice/Activity

Conduction Activities:
Refer to Conductive Heat Transfer Experiments. Experiment should take
approximately 20 minutes if set up before class.

Convection
Activities:
Refer to Convection Heat Transfer Experiments. Experiment should take
approximately 20 minutes if set up before class.

Radiation
Activities:
Refer to Using Radiant Barriers to Learn About Radiation. Experiment should
take approximately 30 minutes if set up before class.

Discuss your
results using the questions and suggestions in each of the labs. Help
students see that what we are typically doing in adding insulation or
installing a radiant barrier is reducing the rate at which one or more
heat transfer mechanisms are occurring.

Also refer back to the Stranded! activity. The Lesson 3 labs
should have given them a better understanding of why some design options
were better than others.

Finally,
run the EnergyGauge Student Edition Base home for your climate
again to review the estimated annual energy use you calculated during
Lesson 2. Then run the Efficient Envelope home that has high levels of
insulation, better windows, better doors and lower infiltration to see
how much the annual energy use is reduced. Then starting with the Base
home again, run each improvement separately (e.g. run Base home after
changing the ceiling insulation from R-1 to R-19, then to R-45; then change
wall insulation…) to see how the improvements change the building
energy use (have the students keep track energy use and energy cost reductions).
Alternatively, as a contest or more informally, have students guess which
improvements will produce the greatest benefits. Discuss your results,
tying in how the improvements are reducing conductive, convective and/or
radiative heat transfer to or from the home.

Feedback

Take several
minutes to review Advance Organizer slide number four (Improving the Building
Envelope), and answer any questions. Discuss how the Lesson 3 activities
might be applied to the “stranded hut”. Tell students that
the next lesson will be on Additional Improvements (HVAC) and (optionally)
assign “history of air conditioning” web research homework
(as described below in the next section).

Handouts and Worksheets

Supply
lab activity instructions to students.

[Optional
homework for Lesson 4] Find
a web site with information on the history of air conditioning. Read
the information, print the web page and bring it to class.